Both characters were redesigned in KoF '99. In every new instalment of the KoF series, Clark seems to be further and further differing from Ralf while Clark is a powerful grappler, Ralf is more of a power player, making use of some very efficient long-range attacks.
In KoF '94, Ralf and Clark were very similar in looks and move repertoire, but by 1995, Clark got a newer stance and win pose, while Ralf retained his old ones. Ralf, and his fellow agent (and good friend), Clark Still, started out as palette swap characters in Ikari Warriors. In order to differentiate the duo, the designers gave Ralf a bandana and Clark a hat, then later sunglasses. But the higher ups ordered them to update their designs to look a little more modern. During the early stages of KoF '94, the development team intended Ralf and Clark to be shirtless in order to express the feeling of 'Ikari' or rage. Keiko Ijuu states that his visual appearance in Ikari Warriors was based on Sylvester Stallone's role as Rambo, which was popular at the time of his conception.
